Resolving page references in layout dependent documents

Abstract

A method for resolving references in electronic documents (EDs), including: obtaining an ED having a reference to an item; generating, based on the ED, an intermediate document (ID) for input to a layout engine; identifying an entry having an initial value for the reference; calculating, during a first rendering of the ED, a first page having the item based on the ID and the initial value substituted for the reference; populating the entry with a first page number corresponding to the first page; calculating, during a second rendering of the ED, a second page having the item based on the first page number substituted for the reference; populating the entry with a second page number corresponding to the second page; and generating, in response to the first page number equaling the second page number, a first rendered document based on the second page number substituted for the reference.

1 . A method for resolving references in electronic documents (EDs), comprising:
 obtaining an ED comprising a reference to an item within the ED;   generating, based on the ED, an intermediate document (ID) for input to a layout engine;   identifying, within a data structure external to the ID, an entry comprising an initial value for the reference;   calculating, by the layout engine and during a first rendering of the ED, a first page comprising the item based on the ID and the initial value substituted for the reference;   populating the entry with a first page number corresponding to the first page;   calculating, by the layout engine and during a second rendering of the ED, a second page comprising the item based on the ID and the first page number substituted for the reference;   populating the entry with a second page number corresponding to the second page; and   generating, using the layout engine and in response to the first page number equaling the second page number in the entry, a first rendered document (RD) based on the ID and the second page number substituted for the reference.   
     
     
         2 . The method of  claim 1 , wherein the ED is defined using an extensible markup language. 
     
     
         3 . The method of  claim 1 , wherein the ED is obtained by a page rendering device (PRD) and wherein the PRD comprises the layout engine and the data structure. 
     
     
         4 . The method of  claim 1 , further comprising:
 identifying, within the ED, an occurrence of a page break associated with a user application; and   setting, before calculating the first page, the initial value in the entry based on the page break.   
     
     
         5 . The method of  claim 1 , further comprising:
 modifying, in response to the first page number equaling the second page number, the ED to include the second page number for the reference; and   generating a second RD for the ED using the second page number as the initial value.   
     
     
         6 . The method of  claim 1 , wherein the data structure is an array. 
     
     
         7 . The method of  claim 1 , wherein the ED comprises a table of contents, and wherein the table of contends comprises the reference. 
     
     
         8 . A non-transitory computer readable storage medium storing instructions for resolving references in electronic documents (EDs), the instructions comprising functionality to:
 obtain an ED comprising a reference to an item within the ED;   generate, based on the ED, an intermediate document (ID) for input to a layout engine;   identify, within a data structure external to the ID, an entry comprising an initial value for the reference;   submit, to the layout engine, the ID and the initial value substituted for the reference, wherein the layout engine calculates a first page comprising the item during a first rendering of the ED;   populate the entry with a first page number corresponding to the first page;   submit, to the layout engine, the ID and the first page number substituted for the reference, wherein the layout engine calculates a second page comprising the item during a second rendering of the ED; and   populate the entry with a second page number corresponding to the second page; and   generate, in response to the first page number equaling the second page number, a rendered document (RD) based on the ID and the second page number substituted for the reference.   
     
     
         9 . The non-transitory computer readable storage medium of  claim 8 , wherein the ED is defined using an extensible markup language. 
     
     
         10 . The non-transitory compute readable storage medium of  claim 8 , wherein the ED is obtained by a page rendering device (PRD) and wherein the PRD comprises the layout engine and the data structure. 
     
     
         11 . The non-transitory computer readable storage medium of  claim 8 , the instructions further comprising functionality to:
 identify, within the ED, an occurrence of a page break associated with a user application; and   set, before calculating the first page, the initial value in the entry based on the page break.   
     
     
         12 . The non-transitory computer readable storage medium of  claim 8 , the instructions further comprising to:
 modify, in response to the first page number equaling the second page number, the ED to include the second page number for the reference; and   generate a second RD for the ED using the second page number as the initial value.   
     
     
         13 . The non-transitory computer readable storage medium of  claim 8 , wherein the data structure is an array. 
     
     
         14 . The non-transitory computer readable storage medium of  claim 8 , wherein the ED comprises a table of contents, and wherein the table of contents comprises the reference. 
     
     
         15 . A system for resolving references in electronic documents (EDs), comprising:
 a hardware processor;   a convertor module executing on the hardware processor and configured to generate an intermediate document (ID) based on an electronic document (ED) comprising a reference to an item within the ED;   a layout engine executing on the hardware processor and configured to:
 calculate, during a first rendering of the ED, a first page comprising the item based on the ID and an initial value substituted for the reference; and 
 calculate, during a second rendering of the ED, a second page comprising the item based on the ID and a first page number corresponding to the first page substituted for the reference; and 
   a data structure external to the ID and comprising an entry storing the initial value, the first page number, and a second page number corresponding to the second page,   wherein the layout engine is further configured to generate a rendered document (RD) based on the ID and the second page number substituted for the reference in response to the first page number equaling the second page number.   
     
     
         16 . The system of  claim 15 , wherein the ED is defined using an extensible markup language. 
     
     
         17 . The system of  claim 15 , further comprising:
 a user application configured to record an occurrence of a page break in the ED,   wherein the initial value is set based on the page break.   
     
     
         18 . The system of  claim 15 , wherein the layout engine is further configured to:
 modify, in response to the first page number equaling the second page number, the ED to include the second page number for the reference; and   generate a second RD for the ED using the second page number as the initial value.   
     
     
         19 . The system of  claim 15 , wherein the convertor module, the layout engine, and the data structure are located on a page rendering device. 
     
     
         20 . The system of  claim 15 , wherein the ED comprises a table of contends, and wherein the table of contends comprises the reference.